Balthazar, in his human form looks like a youthful man in his 30's. He wears a blue suit similar to Gabriel's. He has a habit of changing his ties and picking the worst ones that don't match his suit at all. Balthazar has brown hair and brown eyes. Very thin lips, not very pale skin and rather thick eyebrows. His hair is pulled back, leaving his face clear. He carries a coin with him, which he flips in his fingers when he is excited. Balthazar's eyes change colour depending on his mood, becoming bright red.

Balthazar, in his demon form, has a green, narrow tone to his skin. Demon half-breeds get affected by holy water, which reveals their true form, and burns at the slightest touch. The smell of sulfur reveals their true form, and bare skin is shown.

Balthazar is sadistic, cruel, narcissistic and evil just like almost any other demon would be. He enjoys the pain of others, especially John and only to see negative emotions from him, he tends to do evil things, such as mocking him, killing his allies and many other things. Balthazar gets really amused when there's trouble. Even more so when he is the cause of it. He also gets amused when John is unhappy or angry.

Whenever he's excited or amused, he flips a coin on the fingers of his right hand. Balthazar is prone to deception from others quite easily, not knowing when someone is bluffing or when they're trying to use him. He falls into traps easily and tends to underestimate his opponents. He has been fooled both by Gabriel and by John, as shown when he broke the rules of Hell just to simply allow Gabriel (a half-breed) to release Mammon. He was fooled by John when he believed that John would make him go to Heaven. By that, Balthazar was forced to reveal a secret that soon lead to his death.

He appears to be a sociopath (not that it isn't common in Demons and Angels). His sociopathic tendencies are exhibited when he takes the risk of killing Hennessy, although he wasn't a threat, and just to hurt John. Beeman, though, had to die since he was the only one who could reveal the secret of Mammon's birth, and since he was ordered by Gabriel to keep it a secret, he killed Beeman.

Superhuman Strength - Half-Breeds are able to casually overpower humans with little-to-no effort.

Superhuman Durability - Half-Breeds can survive injuries that would normally kill a human.

Influence - A whisper from a half-breed can either inspire courage, or turn your favorite pleasure into your worst nightmare.

Reality Warping - Displayed when Balthazar killed both Henessi and Beeman. Allows the Demon to manipulate reality to their liking, whether it be filling someone full of flies, or nullifying the effect of gravity on liquids.

The name, Balthazar, belonged to one of the Magi (The Three Wise Men) that met the baby Jesus at the Epiphany.

It is also the name of an Angel in the television series, Supernatural, which coincidentally has much in common, with Constantine's source material, the Hellblazer comic books.

Balthazar's way of killing Beeman was similar to the way Beelzebub would kill. Since Beelzebub is said to be the Lord of the Flies.

Balthazar likes to toy with a coin when he is amused.

Balthazar changes his ties quite often.

He likes bottled liquids.

Balthazar's fear of death is a consequence of his betrayal, he aided Gabriel in his mission of release Mammon and thus, betrayed Lucifer. As a result of his actions, Balthazar will be deported to hell in the event of his death.

Balthazar is the name of a wine bottle. It may link to his liking of bottled beverages.

His scorched face and ablity to flip a coin is extremly similar to that of Two-Face of the Batman franchise.